Self-developing camera apparatus



Sept. 27, 1949.

E. H. LAND ETAL 2,483,014 SELF-DEVELOPING CAMERA APPARATUS Filed Dec. 6,1947 2 Sheets-Sheet l' Sept. 27, 1949. E. H. LAND ETAL SELF-DEVELOPINGCAMERA APPARATUS 2 Sheets-Sheet 2 Filed Dec. 6, 1947 dam/M PatentedSept. 27, 1949 SELF-DEVELOPING CAMERA APPARATUS Edwin H. Land, CambridBelmont, and David assignors to Polaroid 8 Claims.

This invention relates to photographic apparatusfor exposing a layer ofphotosensitive material to record thereon an image of an object and forprocessing said. photosensitive layer wherein. a: liquid. is spread in alayer of predetermined thickness between two sheets of flexiblematerial, one of. which is said photosensitive material.

There is disclosed. in. application, Serial No. 576,254 filed February5, 1 945 by Edwin H. Land for Photographic process, apparatus. and prodact, now abandoned, a method of processing a photosensitive layer byspreading a thin layer of aliquid containing. one or more photographicreagents, or which is a solvent for a photographic reagent, betweensaid. photosensitive layer and a second layer of material. The liquidmay be of a type adapted to enter into a reaction with thephotosensitive layer, e. g., a liquid adapted to cause the developmentof a latent image in a silver halide emulsion. layer and may also causethe formation. of a positive image on the second layer of material. Itis desirable in practicing the inventionv disclosed in theabove-mentioned application Serial No. 576 254 that the layer of liquidspread between the photosensitive layer and the second layer of materialbe of a uniform predetermined thicknesstoinsure that-every unit area ofthe photosensitive material. and the second layer of material is. incontact with a predetermined quantity of the liquid.

object of thepresent invention is to provide a photographic apparatusfor spreading a liquid photographic reagent or solvent for aphotographic reagent in a layer of predetermined uniform thicknessbetween an exposed photosensitive surface and another surface whereinthe speed with. which. the liquid is spread and/or the viscosity ofsaid. liquid does not affect the thicknessof the layer of liquid to anyappreciable degree.

Another object of the present invention is to provide a photographicapparatus for carrying out the process, of spreading a liquidphotographic reagent or. solvent for a photographic reagent in. a layerof predetermined uniform thickbetween a photosensitive layer comprisingone surface of a sheet of deformable material and the surface of asecond. sheet of deformable material. wherein variations in thethickness of P the layers of sheet. material cause only minor variationsin the thickness of the layer of liquid.

A. further object ofthe present invention is to provide a photographic.apparatus, comprising a slot having a fixed predetermined width,

ge, Murry N. Fairbank,

. Grey, Weston, Mass.,

Corporation, Cambridge, Mass, a corporation of Delaware ApplicationDecember .6, 1947, Serial'No. 790,064

adapted to carry out the process of spreading a liquid photographicreagent or solvent for a photographic reagent in a layer ofpredetermined uniform thickness between a photosensitive layercomprising one surface of a sheet of deformable material and the surfaceof a second sheet of deformable material wherein said sheets ofmaterial. are drawn through said slot to spread a layer of liquidthinner than the difference. between the width of said slot and thetotal thickness of said sheetlike materials.

A further object of the present invention is to. provide a photographicapparatus for carrylng. out the process of spreading a liquidphotographic reagent or solvent for a photographic reagent in a layer ofpredetermined uniform thickness between a photosensitive layercomprising one surface of a sheet of deformable material and the surfaceof a second sheet of deformable material wherein the speed with whichthe liquid is spread and/or the viscosity of the liquid does not affectthe thickness of the layer of liquid to any appreciable degree andwherein variations in the thickness ofeither of the sheet materialscause only minor variations in the thickness of the layer of liquid.

A further object of the present invention is to provide a photographicapparatus for carryingout the process wherein a liquid compositioncontaining a photographic reagent or a solvent for a photographicreagent is spread in a layer of predetermined uniform thickness betweena layer of photosensitive material having a latent n gative imageformed. therein and a second layer of material adapted to receive avisible positive image of said latent image and wherein the speed withwhich said liquid composition is spread does not affect the thickness ofsaid liquid layer to any appreciable degree.

other objects of the invention will inv part be obvious and will in partappear hereinafter.

The invention accordingly comprises the apparatus possessing. theconstruction, combination of elements and arrangement of parts which areexemplified in the following detailed, disclosure, and the scope of theapplication of which will be indicated in the claims.

For a fuller understanding of the nature and objects of the invention,reference should be had to the following detailed description taken inconnection with the accompanying drawings wherein:

Figure l is a diagrammatic view of one form of apparatus embodying thepresent invention;

Figs. .2 and Bare diagrammatic sectional views illustrating one form ofpressure-applying means capable of forming a part of the apparatus ofFig. 1 and illustrating one way in which the photographic reagent, or asolvent therefor, can be positioned between the two sheetlike materials;

Fig. 4 is a diagrammatic sectional view illustrating a modified form ofpressure-applying means;

Fig. 5 is a diagrammatic sectional view of another form ofpressure-applying means wherein two spaced rollers are employed tospread a liquid between two sheetlike materials; and

Fig. 6 is a diagrammatic sectional view of yet another form ofpressure-applying means wherein a roller and a fixed backing member areemployed to spread a liquid between two sheetlike materials.

Fig. '7 illustrates an alternate form of pressure-applying means.

The present invention provides a photographic camera apparatus capableof exposing a sheet of photosensitive material to actinic light andspreading a liquid between the surface of said photosensitive materialand another layer of material in a uniform layer of predeterminedthickness. The sheet of photosensitive material may comprise anyphotosensitive material as, for example, silver halide.

The other layer of sheetlike material preferably comprises a surfaceadapted to receive a visible positive image of a latent negative imageformed in said photosensitive material. The liquid preferably is quiteviscous and comprises a reagent which preferably contains at least asolvent for a substance capable of differentially reacting with portionsof said exposed photosensitive material to create a visible effecttherein and preferably capable of being transferred to said other layerof sheetlike material to form a visible positive image. The apparatus issimple, reliable, easy to operate and results in a layer of liquidcomposition of a predetermined desired thickness regardless of the speedwith which said composition is spread and/or the viscosity of the liquidcomposition.

One form of a camera apparatus embodying the present invention is showndiagrammatically in Fig. 1. The camera disclosed in Fig. 1 comprises abellows i0, lens and shutter assembly 12 and an upper compartment M forholding a roll l5 of photosensitive sheet material [8. Thephotosensitive material i8 is adapted to be drawn from the roll is andpass in back of an exposure aperture 29 in back of the lens and shutterassembly at which point the photosensitive material la is adapted to beexposed to actinic light to have formed therein a latent negative image.After passing the exposure aperture 20, the photosensitive material l8passes into a lower compartment 22 which is adapted to hold a cartridge26 which carries a roll of sheetlike material 24- which, in turn, hasliquid-carrying containers 28 adhesively secured thereto at regularpredetermined intervals greater than the length of said exposureaperture. An opening or slot 30 is provided in the bottom of the lowercompartment 22 to permit the photosensitive layer l8 and the sheetlikematerial 24 to be drawn from the camera. A pair of novelpressure-applying liquid-spreading members 32, which will subsequentlybe explained in detail, are located in the lower compartment 22 adjacentthe slot so that after the photosensitive layer l8 has been exposed itand the sheetlike material 24 are advanced with respect to saidspreading members 32 out of said compartment 22 to rupture the container28 and spread the contained liquid in a uniform predetermined layerbetween said photosensitive material iS and sheetlike material 24 asthey are advanced together between members 32 and out of the camera. Theentire back of the camera including the upper compartment 14, theportion in back of the exposure aperture 20 and the lower compartment 22are enclosed by a cover 34 which is hingedly attached to the edge of theupper compartment I4. Light seals 36 are provided in the slot 38,between the lower compartment 22 and the exposure aperture 20, andbetween the upper compartment I4 and the exposure aperture 29 to preventunwanted actinic light from leaking into the camera to fog thephotosensitive layer H3.

The pressure-applying members employed in the photographic apparatus ofthe present invention for spreading a liquid between the interfacesurfaces of the exposed photosensitive material and a second sheetlikematerial comprise two substantially rigid members mounted in spacedrelation to each other so as to prevent, for all practical purposes, anymovement toward or away from each other to form a fixed gap or slot ofsubstantially the same width throughout its length. The surfaces of thesubstantially rigid members which form the fixed gap or slot which arecontacted by the outer surfaces of the sheetlike materials as they areadvanced through said gap or slot are shaped to form an entrance orthroat which together with the sheetlike materials which are caused toconform thereto cause a pressure to build up within the liquid betweensaid sheetlike members. The pressure thus generated causes apredetermined quantity of said liquid to pass through the gap or slotwith each unit area of said sheetlike materials to form the desiredliquid layer therebetween. For a given pressure, the quantity of liquidwhich will pass through a given gap or slot is an inverse function ofthe viscosity of said liquid, i. e., as the viscosity of the liquidincreases, the quantity of the liquid passing through said gap or slotwill decrease. For a given viscosity, the quantity of liquid which willpass through a gap or slot is a function of the pressure generated insaid liquid, 1. e., as the pressure increases, the quantity of liquidpassing through said gap or slot increases. The pressure generated inthe liquid is a function of the speed at which the sheetlike materialsare drawn through a given gap or slot and the viscosity of the liquid,i. e., the pressure generated within the liquid increases as the speedat which the sheetlike materials are advanced through the gap or slotincreases and/or as the viscosity of the liquid increases. The oppositeis also trueas speed and viscosity decrease, the hydraulic pressuredecreases.

The preferred embodiments of the pressureapplying members of the presentinvention are proportioned to utilize the above characteristics to suchan extent that a layer of liquid having a substantially uniformpredetermined thickness is spread between the two sheetlike materialsiiidependently of the speed at which said sheetlike materials areadvanced between said pressure-applying members and the viscosity of theliquid. This is possible because an increase in viscosity would resultin less liquid passing through the gap or slot, but an increase inviscosity causes the hydraulic pressure generated to increase and theincreased pressure causes sub- .sta-n-tially the same quantity of liquidto pass =through the slot or gap per unit area of sheet- :like materialas passed through before the vis- ;:throughthe slot of gap per unit areaof .sheetlike material as passed through before the speed was increased.

The preferred embodiments of the photograph- :ic apparatus of thepresent invention :employ the principle set forth above in generating apres- :sure in the'liq-uid which is of such a magnitude, .in relation tothe Speed with which the sheet-like materials are advanced through theslot or gap, that the layeroi liquid spread between the sheetlike.materials is thinner than the difference between the total thickness ofthe two layers of sheetlike materials and the width of the slot or gap.This is preferred so that variations in either. or both of the sheetlikematerials will .cause. only minor variations, which are withinacceptable limits, in the thickness of the liquid layer.

In the practice of the present invention it is preferred to shape thethroat portion of the slot or;ga-prs that the thickness of the layer ofliquid deposited between the two sheetlihe materials will beone-thirclto two-thirds of the difference between the total thickness of the twolayers of sheetlike materials and the width of the slot or :gap. Forexample, if the throat and slot or gap :are shaped to give a ratio ofreduction that is three to one and the minimum width of the slot or gapis such that the dilierence between the total thickness of the twolayers of sheetlike materials and said minimum width is substantially.003 inch a layer of liquid composition substantially .001 inch thickwill be spread. If the ratio of reduction is three to two the samespacing will spread layer of liquid substantially :062 inch thick.Therefore, if the thickness of one f thesheetlilre materials should varyat a given area the variation in the thickness of the liquid layer willonly be a fraction of that variation. For example, if one of thesheetlik-e materials should be .001 inch thicker than desired at somearea or spot, so that the difierence between the total thickness of saidsheetlike materials and the minimum width of the slot or gap at thatarea or spot is only .002 inch, the thickness of the liquid layer spreadon that area :or spot will be .00856 inch thick if the slot or gap has aratio of reduction of three to one. If the slot or gap has a ratio ofreduction of three to two the same variation in the sheetlike materialwould result .in a liquid layer @0133 inch thick.

Figs. 2 and 3 are enlarged diagrammatic views of the pressure--applyingmeans, comprising two substantially rig-id bars 32 employed in thephotographic apparatus of Fig. 1 for spreading a liquid between twosheetlike materials. Figs. .2 also illustrate the manner in which aliquid-car- :rying container 2.8 releasably carrying a predeterminedquantity of liquid composition may be employed to deposit apredetermined quantity of liquid composition between the interiace sur-7 .faces of the sheetlike materials is and .24. Each of thesubstantially similar rigid bars .32 comprises a flat portion .38 and aleading edge 40 fixedly mounted in spaced relation to each other withthe .fiat portions '38 in tace-to-face relation and .3 1

to rprovideaslot or gap 42.. Two sheets of flexible material is and 24,having a supply of liquid M therebetween, are shown being drawn throughthe slot or gap :42 in the direction of the arrow 3 spread the liquid 44in a layer of uniform predetermined thickness between the sheets i8 and2:1. The sheet of material It comprises an inner layer 19 which maycomprise any photosensitive :mater-ial as, for example, silver halidewhich is carried by .a base layer 21 which may comprise any flexiblesheet material as, for example, paper, cellulose acetate, or cellulosenitrate. The sheet of material 24 may compriseany flexible material as,for example, paper, thin wood, metal, plastic, or the material known tothe art as .baryta paper. The liquid 44 may comprise a solvent foraphotographic reagent or it may include a photographic reagent. In onesatisfactory form of the embodiment disclosed in Figs. 2 and 3 theleading edges 40 which form the throat of the slot .or gap 42 curveoutwardly f om the fiat portions 38. in the arcof a circle preferablyhaving a radius of substantially inch. The width of the gap or slot 42is preferably substantially .023 inch so that when sheet materials i8and 2-4, having a total thickness of substantially .029 inch, are drawntherethrough the difference between the width of the gap or slot 42 andsaid total thickness is substantially .003 inch. When this form of theembodiment of 2 and 3 is employed to spread a liquid 44, having aviscosity of from 1000 centipoises to 200,030 centipoises, between twosheet materials =18 and 2 whose combined thickness totals substantially.020 inch 'a pressure will be generated said liquid 44 which will causea layer of said liquidtd substantially .001 inch thick to be spreadbetween said two sheet materials H5 and -24. The radius of the leadingedges 40 may be increased .or decreased to vary the thickness of thelayer of liquid 44 which will be spread. When the radius of the leadingedges 45 is increased the thickness of the layer of liquid will beincreased with increase in the width of the slot or gap 1.2. This isbecause increasing the radius of the leading edges 40 decreases theangle of the throat which results in a higher pressure-to-speed ratiothan is the case with a smaller radius of curvature. The higherpressure-to-speed ratio results in a larger quantity of liquid 44 beingforced through the gap or slot 52 for each unit area of the sheetmaterials 48 and 2!; to give a thicker layer of liquid. By the sametoken, when the radius of curvature of the leading edges 40 is reducedthe angle of the throat is increased resulting in a lowerpressure-to-speed ratio :and a smaller quantity of liquid passingthrough the slot or gap 42 .for each unit area of sheet materials i8 and2-4 with the result that a thinner layer of liquid is spread for thesame width of the gap or slot 42.

A liquid-carrying container 2 3 releasably carrying a predeterminedquantity of liquid composition is positioned between the interfacesurfaces of the sheet materials 58 and 24 adjacent to the areas thereonbetween which it is desired to spread said liquid. The liquidwarryingcontainer 28 maybe placed between the sheetlike materials 18 and 24after they have been started through the slot or gap 42, but it ispreferred to .adhes-ively secure one of said liquid-carrying containers28 to one of said sheetlike materials l8 and 24. The container 28 isadapted upon the application of a mechanical stress thereto as, forexample, compression of the walls thereof, to

open along a predetermined edge to release the contained liquid 44.

The container 28 is preferably made from a sheet of material which isinert and impervious to the contained liquid 44 and also to oxygen andwater vapor as, for example, a multilayer sheet comprising a base layerof kraft paper or fabric, an intermediate layer of metal foil laminatedto said base layer and a third layer of heat-sealing plasticsubstantially impervious and inert to the fluid 44. Preferably, thecontainer 28 is an envelope or saclike structure formed by folding saidmultilayer sheet of material and heat sealing the edges together. Thecontainer 28 is preferably of a length substantially equal to the widthof the sheet materials l8 and 24 so that when placed in the positionillustrated in Fig. 2 it will extend substantially across the width ofsaid sheet materials. The multilayer sheet material used to make thecontainer 28 preferably has a thickness of not greater than one-half thespace between the two sheetlike materials I8 and 24 as they pass throughthe slot or gap 42, and the filled container 28 is substantially thickerthan the space between the sheetlike materials [8 and 24 as they passthrough the slot or gap 42.

It will thus be seen that when the two sheets of material I8 and 24having the liquid-carrying container 28 located therebetween are drawnthrough the slot or gap 42 to pull the liquidcarrying container 28between the barlike members 32 a stress is applied to the walls of saidcontainer '28 by the barlike members 32. This stress generates apressure in the liquid 44 inside of the liquid-carrying container 28 andas the container 28 continues to be drawn into said slot or gap 42 saidpressure becomes high enough to cause the sealed edge 48 of saidcontainer 28 to open and release the liquid 44. Continued movement ofthe sheets 18 and 24 through the slot or gap causes substantially allthe liquid 44 to be squeezed or pressed out of the container 28 anddeposited at the throat portion of the slot or gap 42. After the liquid44 has been removed from the container 28 said container 28 in itscollapsed position passes through the slot or gap and said slot or gapon continued movement of the sheets i8 and 24 therethrough causes theliquid 44 to be spread in a layer of uniform predetermined thicknessbetween the two sheetlike materials in the manner set forth above.

Fig. 4 discloses diagrammatically a modification of the embodimentdisclosed in Figs. 2 and 3 wherein the arc of the leadin edge of theembodiment of Figs. 2 and 3 has been continued to give a semicircularleading edge 50 on each of the rigid bars 52. The embodiment of Fig. 4is adapted for use where it is desired to change the direction of thesheet materials [8 and 24 through 180 before they pass through the slotor gap 42. This modification is also useful with sheet materials thatare somewhat stifi and tend to not conform readily to the configurationof the throat.

Fig. 5 is a diagrammatic showing of another embodiment of apressure-applying means for spreading a liquid between two sheetlikematerials and also adapted for use with the photographic apparatus ofthe present invention, comprising two substantially similar rigidrollers 54 rotatably mounted a fixed distance from each other to providea fixed gap or slot 42.

In one satisfactory form of the embodiment disclosed in Fig. 5 therollers 54 preferably have a diameter of substantially inch and arepreferably so positioned with respect to each other that a gap or slot42 substantially .023 inch wide is provided therebetween. As the sheetmaterials i3 and 24 and the liquid 44, all similar to those disclosed inconnection with the embodiment of Figs. 2 and 3, are drawn through theslot or gap 42, the rollers 54 are rotated by their contact with theouter surfaces of the sheet materials 18 and 24 and a leading edgecomprising an are having inch radius is constantly presented by thecircumference of each roller 54. These leading edges generate a pressurein the liquid 44 which forces said liquid through the slot 42 to form athin layer of uniform predetermined thickness between the sheetmaterials I8 and 24. When sheet materials I8 and 24 and liquid 44, asdescribed in connection with the embodiment of Figs. 2 and 3, are passedthrough the slot or gap 42 between rollers 54 having the abovedimensions, the ratio of the thickness of the layer of liquid depositedbetween the interface surfaces of the layers 18 and 24 to the differencebetween the total thickness of said two layers [8 and 24 and the widthof the slot or gap 42 is substantially three to one so that a liquidlayer .001 inch thick is spread between said interface surfaces.

The diameter of the rollers 54 may be increased or decreased to vary thethickness of the liquid 44 which will be spread. When the diameter isincreased the thickness of the layer of liquid will be increased with noincrease in the width of the slot or gap 42 between the rollers 54. Thisis because increasing the diameter of the rollers 54 decreases the angleof the throat which results in a higher pressure to-speed ratio than isthe case with smaller diameter rollers. The higher pressure-to-speedratio results in a larger quantity of liquid 44 being forced through thegap or slot 42 for each unit area of sheet materials l8 and 24 andtherefore gives a thicker layer of liquid. By the same token, when thediameter of the rollers 54 is reduced, the angle of the throat isincreased resulting in a lower pressure-to-speed ratio and a smallerquantity of liquid passing through the slot or gap 42 for each unit areaof sheet materials I8 and 24 with the result that a thinner layer ofliquid is spread for the same width of slot or gap.

Fig. 6 is a diagrammatic showing of another embodiment of apressure-applying means for spreading a liquid between two sheetlikematerials and also adapted for use with the Photographic apparatus ofthe present invention, comprising a fixed substantially rigid backingplate or bar 56 and a substantially rigid roller 58 rotatably mounted afixed predetermined distance from said plate 55 to provide a gap or slot42 of predetermined uniform width. Sheet materials i8 and 24 and liquid44, as described in connection with the embodiment of Figs. 2 and 3, aredrawn through the slot or gap 42 in the direction of the arrow 45 tospread said liquid 44 between the interface surfaces of said sheetmaterials l8 and 24 in a layer Of uniform predetermined thickness. Ifroller 58 is of the same diameter as the rollers 54 of Fig. 5, it; willcause a thicker layer of liquid to be spread between the sheet membersl8 and 24 than will the two rollers 54 of Fig. 5. This is because thebacking member 56 is fiat and has no leading edge, at least in the sensethat the term leading edge is used in the description of the threepreceding embodiments. This results in a throat portion having a smallerangle than the throat formed by two rollers and, as set forth above,a'low throat'angle gives ahig'her pressureto speed ratiothan a largethroat angle. The "thickness o'fxthe l ayer'of'liqui'd 4'4 spreadbetween the sheet materials l8 and 24 ma be varied by increasing "ordecre'asing'the diameter of the roll 58. An'in'crease in the diameterwill'result in an increase in 'thethicknessof the liquid layer becausesuch increases and decreases change the angle of the throat of the gapor slot 42.

'Whereas the use of .the liquid-carrying container 28 has beenspecifically shown and described in connection with the embodimentdisclosed in Figs. 2 and 3 'itwill be readily appreciated that thecontainer 28 can be used to deposit the liquid composition 44betweenthe'sheetlikematerials i3 and'-2"'4 when any of .the-erhbodiment's disclosed in Figs. 2through-6 are used.

It will also be appreciated that the liquid 44 maybe located'between theinterface surfaces of the sheetlike materials it and 24 in other waysasfifor example, it may be injected between the .two -sheetlilrematerials or it can be spread on the'surface' of either or both of thesheets before theyiare started through the slot or gap 42.

It will also be appreciated that it may be desirable to pass objectshaving greater thickness than the difference between the Width of saidslot or gap4'2 and the total'thickness of the two sheet- "like'materialsl8 and 24 through said slot or gap 42. For example, it might bedesirable'to make the liquid-"carrying container from a thicker sheetmaterial. Iopermit enlarged solid objects ito'pass through the slot orgap 42 between the interface surfaces of the sheetlike materials [8 and24 the two elements forming said gap or slot 42 canbe held apredetermined mini-mum distance apart bymeans of a springiiil strongenough to resist the "pressure generated in the liquid both in rupturingthe container 28 and in spreading the liquid between said sheetlikematerials 18 and '24. Such a spring loading will permit the slot or gap42 to open to pass incompressible objects but remain fixed whilespreading the liquid 44. As shown in Fig. 7, spring 60 is provided in aspreader arrangement which is otherwise generally like that shown inFig. 1.

The apparatus of the present invention has been disclosed primarily inconnection with the processing of a layer of photosensitive materialhaving a latent negative image formed therein by differentially reactinga photographic reagent with said latent image to form visibleimageforming components which are deposited on a second layer ofmaterial to give a visible positive image. The present invention is notlimited to this specific use only but is adapted to other uses as, forexample, to spread a liquid reagent over the surface of anyphotosensitive material to develop and/ or fix a latent or visible imageformed therein, or to spread a liquid reagent over the v 1 surface of aphotosensitive layer prior to exposing it to lightso that .the imageformed by said exposure will be developed and/or fixed without anyfurther processing.

If the photosensitive material It comprises a diazonium photosensitivematerial the liquid reagent i l can be such that it will-developavisible positive image in said material I 8. If the photosensitivematerial l8 comprises astandard silver halide photosensitive materialtheliquid reagent may develop a negative image therein and it may alsofix the negative image. Ina preferred form of the invention the liquidalso creates a positive image of the latent negative =-image--on thesurface of a second sheet of mateill 10 rial. If suchapositive image isdesired a liquid composition is preferably formedwas set forth in thefollowing nonlimiting example:

Ewample 1 Grams Water 1860 Sodium carboxymethyl cellulose 93Sodium-sulfite 78 Sodiumh-ydroxide 74.6 Sodiumthiosulfate 14.5 'Citricacid 38.5 *Hydroquinone s 52.0

Four embodiments of pressure-applying means, each capable of beingincorporated in the photographic apparatus of the present invention,have been disclosed. In two of the embodiments the barlike members arerigidly mounted against rotation so that the sheetlike materials I8 and24 slide across their surfaces as they are advanced through the slot orgap '22. In a third embodiment the b'arlike members are rollersrotatably mounted on fixed axes parallel to each other. In thisembodiment the sheetlike materials l8 and it are, in effect, rolledacross their surfaces as they are advanced through theslot or gap 42, Inthe fourthem-bodiment one ofthe lbarlike members is rigidlyinounted'against rotation and the otheris aroller'rotat-ably mounted ona fixed axis parallel to the first barlike member.

'Each'of the above three types of pressure-applying means has certainadvantages over the other-"two. For'exampla'itis desirable that it bepossible to advance or draw the sheetlike materials it; and through theslot Sit and outof materials '18 and Zilreinain in substantialregistration, i. e., with their respective edges substantially inalignment, as they are advanced 'or drawn out or the camera apparatus.When pressure-applying means which are rigidly mounted against rotation(the embodiments of Figs. 2, '3 and 4) are used, the two sheetlikematerials l8 and 24 remain" in substantial registration as they aredrawn from the camera apparatus but the force required to draw them outis relatively high. Apparently the desired registration is obtainedbecause of "the fact that substantially the same frictional force mustbe overcome to move the 'she'etlike materials in any direction andtherefore any'tendency of either of said sheetlike materials'to creep orwander is overcome by the force drawing it from'the camera apparatus.When roller type pressure-applying means (Fig. 5) are usedythe forcenecessary to draw the sheetlike inat'erialsit 'and'2'4 from the cameraapparatus is relativelylow'but said sheetlike materials have atendencytocreep'or wander'sideways if the roll liijcartridge '28, andpressure-applying means 54 "are "not absolutely parallel. Apparentlythis is because of the factthat a much larger force is necessary toovercome friction and cause said "sheetlike material to slide sidewayson the pressure-applying means to correct the tendency'to creep orwander-than is necessary to draw'said sheetlike-materials out of thecamera apparatus.

Whereas the'modification disclosed in Figs. 2

and 3' has been specifically shown and described in connection with thecamera apparatus of'Fig. '1 it Will be understood that any of themodifica- "tions disclosed in Figs. 4, 5 and 6 may beused therewith.

-Since certain changes may be made in the 75above apparatus withoutdeparting from the 11 scope of the invention herein involved, it isintended that all matter contained in the above description or shown inthe accompanying drawings shall be interpreted as illustrative and notin a limiting sense.

What is claimed is:

1. A photographic apparatus comprising means for positioning an imagearea of a photosensitive layer in position to be exposed to actiniclight modified by a subject image and for releasably holding a secondlayer of material, said means so positioning said layers with respect toeach other that said layers can be drawn therefrom in faceto-facerelation, two substantially parallel rigid members spaced from eachother a predetermined distance, said parallel members being sopositioned with respect to said means that said two layers can be drawntherebetween in face-to-face relation, the space between said parallelmembers comprising a pressure-generating throat whereby a hydraulicpressure can be generated in a liquid located between said layers tospread said liquid between the interface surfaces of said layers as theyare drawn between said members, and means for maintaining said membersspaced, in their operative position, by a distance greater than thecombined thickness of the two layers between which said liquid isspread, said last-named means applying a suficient holding force to saidparallel members to keep the same from moving apart under the influenceof the hydraulic pressure generated during the spreading.

2. A photographic apparatus comprising means for positioning an imagearea of a photosensitive layer in position to be exposed to actiniclight modified by a subject image and for releasably holding a secondlayer of material, said means so positioning said layers with respect toeach other that said layers can be drawn therefrom in face-to-facerelation, two substantially parallel rigid members spaced from eachother a predetermined distance, said parallel members being fixedagainst rotation and being so positioned with respect to said means thatsaid two layers can be drawn therebetween in face-to-face relation, thespace between said parallel members comprising a pressure-generatingthroat whereby a hydraulic pressure can be generated in a liquid locatedbetween said layers to spread said liquid between the interface surfacesof said layers as r they are drawn between said members, and means formaintaining said members spaced, in their operative position, by adistance greater than the combined thickness of the two layers betweenwhich said liquid is spread, said last-named means applying a sufiicientholding force to said parallel members to keep the same from movingapart under the influence of the hydraulic pressure generated during thespreading.

3. A photographic apparatus comprising means for positioning an imagearea of a photosensitive layer in position to be exposed to actiniclight modified by a subject image and for releasably holding a secondlayer of material, said means so positioning said layers with respect toeach other that said layers can be drawn therefrom in face-to-facerelation, two substantially parallel rigid members spaced from eachother a predetermined distance, said parallel members being sopositioned with respect to said means that said two layers can be drawntherebetween in face-toiace relation, a curved surface on one of saidparallel members forming a pressure-generating throat in the spacebetween said parallel members whereby a hydraulic pressure can begenerated in a liquid located between said layers to spread said liquidbetween the interface surfaces or said layers as they are drawn betweensaid members, and means for maintaining said members spaced, in theiroperative position, by a. distance greater than the combined thicknessof the two layers between which said liquid is spread, said last-namedmeans applying a sufficient holding force to said parallel members tokeep the same from moving apart under the influence of the hydraulicpressure generated during the spreading.

4. A photographic apparatus comprising means for positioning an imagearea of a photosensitive layer in position to be exposed to actiniclight modified by a subject image and for releasably holding a secondlayer of material, said means so positioning said layers with respect toeach other that said layers can be drawn therefrom in face-to-facerelation, two substantially parallel rigid members spaced from eachother a predetermined distance, said parallel members being fixedagainst rotation and being so positioned with respect to said means thatsaid two layers can be drawn therebetween in face-to-face relation, eachof said parallel members having a curved surface and a flat surface,said curved surfaces cooperating to form a pressure-generaating throatin the space between said parallel members whereby a hydraulic pressurecan be generated in a liquid located between said layers to spread saidliquid between the interface surfaces of said layers as they are drawnbetween said members, and means for maintaining said members spaced, intheir operative position, by a distance greater than the combinedthickness of the two layers between which said liquid is spread, saidlast-named means applying a sufficient holding force to said parallelmembers to keep the same from moving apart under the influence of thehydraulic pressure generated during the spreading.

5. A photographic apparatus comprising means for positioning an imagearea of a photosensitive layer in position to be exposed to actiniclight modified by a subject image and for releasably holding a secondlayer of material, said means so positioning said layers with respect toeach other that said layers can be drawn therefrom in faceto-facerelation, two substantially parallel rigid members spaced from eachother a predetermined distance and rotatably mounted, said parallelmembers being so positioned with respect to said means that said twolayers can be drawn therebetween in face-to-face relation, a portion ofthe space between said parallel members comprising a pressure-generatingthroat whereby a hydraulic pressure can be generated in a liquid locatedbetween said layers to spread said liquid between the interface surfacesof said layers in a uniform layer of predetermined thickness which isthinner than the difference between said space and the total thicknessof said first-mentioned two layers as said two layers are drawn betweensaid members, and means for maintaining said parallel members in saidspaced relationship, said last-named means applying a sufficient holdingforce to said parallel members to keep the same from moving apart underthe influence of the hydraulic pressure generated during the spread- 6.A photographic apparatus comprising means for positioning an image areaof a photosensitive layer in position to be exposed to actinic lightmodified by a subject image and for releasably holding a second layer ofmaterial, said means so positioning said layers with respect to eachother that said layers can be drawn therefrom in face-to-face relation,two substantially parallel rigid members spaced from each other apredetermined distance, said parallel members being so positioned withrespect to said means that said two layers can be drawn therebetween inface-toface relation, the space between said parallel members comprisinga pressure-generating throat whereby a hydraulic pressure can begenerated in a rupturable liquid-carrying container located between saidlayers to rupture said liquidcarrying container to release the containedliquid and to spread said liquid between the interface surfaces of saidlayers as they are drawn between said members, and means for maintainingsaid members spaced, in their operative position, by a distance greaterthan the combined thickness of the two layers between which said liquidis spread, said last-named means applying a sufficient holding force tosaid parallel members to keep the same from moving apart under theinfluence of the hydraulic pressure generated during the spreading.

'7. A photographic apparatus comprising means for positioning an imagearea of a photosensitive layer in position to be exposed to actiniclight modified by a subject image and for releasably holding a secondlayer of material having mounted thereon a rupturable liquid-carryingcontainer, said means so positioning said layers with respect to eachother that said layers can be drawn therefrom in faceto-face relationwith said rupturable liquid-carrying container located between theirinterface surfaces, two substantially parallel rigid members spaced fromeach other a predetermined distance, said predetermined distance beinggreater than the total thickness of said two layers but less than thetotal thickness of said two layers and said rupturable liquid-carryingcontainer, said parallel members being so positioned with respect tosaid means that said two layers can be drawn therebetween in faceto-facerelation, the space between said parallel members comprising apressure-generating throat whereby a hydraulic pressure can be generatedin the liquid carried by said liquid-carrying container to rupture andrelease said contained liquid and to spread said liquid between theinterface surfaces of said layers as they are drawn between saidmembers, and means for maintaining said parallel members in their spacedrelationship, said last-named means applying a sufficient holding forceto said parallel members to keep the same from moving apart under theinfluence of the hydraulic pressure generated during the spreading ofthe liquid.

8, A photographic apparatus comprising means for positioning an imagearea of a photosensitive layer having mounted thereon a rupturableliquid-carrying container in position to be exposed to actinic lightmodified by a subject image and for releasably holding a second layer ofmaterial, said means so positioning said layers with respect to eachother that said layers can be drawn therefrom in face-to-face relationwith said rupturable liquid-carrying container located between theirinterface surfaces, two substantially parallel rigid members spaced fromeach other a predetermined distance, said predetermined distance beinggreater than the total thickness of said two layers but less than thetotal thickness of said two layers and said rupturable liquid-carryingcontainer, said parallel members being so positioned with respect tosaid means that said two layers can be drawn therebetween inface-to-face relation, the space between said parallel memberscomprising a pressure-generating throat whereby a hydraulic pressure canbe generated in the liquid carried by said liquid-carrying container torupture and release said contained liquid and to spread said liquidbetween the interface surfaces of said layers as they are drawn betweensaid members, and means for maintaining said parallel members in theirspaced relationship, said last-named means applying a sufficient holdingforce to said parallel members to keep the same from moving apart underthe influence of the hydraulic pressure generated during the spreadingof the liquid.

EDWIN H. LAND. MURRY N. FAIRBANK. DAVID S. GREY.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,424,816 Grillone Aug. 8, 19221,758,326 Langsner May 13, 1930

